Diffusion Analyses along Mean and Gaussian-Curved Membranes with CurD

Area of Science:

• Biophysics
• Computational Biology
• Cell Biology

Background:

• Curved cellular membranes are vital for biological functions.
• Understanding lipid and macromolecule diffusion on these membranes is experimentally challenging.
• Existing models struggle to differentiate geometric effects from property changes induced by curvature.

Purpose of the Study:

• To address the lack of computational tools for analyzing diffusion on curved membranes.
• To introduce CurD, an open-source implementation of the Vertex-oriented Triangle Propagation algorithm.
• To investigate the distinct roles of mean and Gaussian curvature on lipid diffusion.

Main Methods:

• Developed and implemented the CurD algorithm for calculating geodetic distances on curved surfaces.
• Utilized coarse-grained molecular simulations of lipid diffusion.
• Applied the CurD tool to analyze diffusion dynamics on membranes with varying mean and Gaussian curvature.

Main Results:

• CurD significantly accelerates the computation of geodetic distances compared to traditional methods.
• Analysis revealed that Gaussian curvature has a minimal effect on lipid motion.
• Mean curvature, related to lipid headgroup packing, is the primary determinant of lipid mobility.

Conclusions:

• CurD provides a novel and efficient method for studying diffusion on curved membranes.
• The findings highlight the dominant role of mean curvature in regulating lipid diffusion.
• This work offers insights into membrane dynamics relevant to physiological processes like endocytosis.